Patent GB-917875-A (GB)
Title: Improvements in or relating to photographic type composing
IPC: B41B21/08
Filed: 1958-12-29
Abstract: 917,875. Photographic type composing; photographic projection printers. JACOMELLI, L. B., [trading as D.E.I.-TIPOGRAFIA DEL GENIO CIVILE]. Dec. 29, 1958 [Dec. 30, 1957], No. 41839/58. Class 98 (1). Titles, inscriptions and legends are composed photographically by projecting on a strip of light sensitive paper or film images of letters or marks recorded on a negative film and varying the exposure time in accordance with the body size and face of the projected letter or other type symbol. As shown, a type symbol matrix film fed between spools 1,2 around a drum rotatable on a fixed shaft 7 and provided with a transparent cylindrical portion 4 carries four fonts with the same symbol in each font aligned parallel to the drum axis, the drum and spools 1, 2 being connected by a driving belt 12. The desired font is brought into line with a slot aperture 27 of a width and height to accommodate only one symbol in any one row on the matrix film, receiving an illuminating beam from a fixed; lamp 25, by means of a cam 9 which is fixed to a shaft 9<SP>1</SP> and controls the vertical position of the drum the shaft 7, and the character required is selected from the selected font row by rotating a hand wheel 8 secured to the drum and carrying a pointer 10 co-operating with a concentric dial bearing the  type symbol indications placed on the upper face of the machine. The cam 9 may be moved to a fifth position in which the drum descends so that the fixed pegs 16 (displace the balls 17 within the sleeves 15 and so free the disc from the drum. Beneath the drum and frictionally engaged with depending sleeves 15 thereon by balls 17 is a disc 13 rotatably mounted on the fixed shaft 7 so that disc and drum normally rotate together The disc bears triangular teeth 13<SP>1</SP>, in which a fine-positioning and latch ing member 21 operated by an electromagnet 22 engages, and carries a metal ring 14 supporting concentric rings of hemispherical contacts 14<SP>1</SP>; each radial group corresponding to one symbol on the matrix film Also supported on the shaft 7 but held against rotation by pins 16 on a fixed base member 19 is an arm 20 bearing contacts 20<SP>1</SP>, one for engaging each ring of contacts 141 and one directly engaging the ring 14. An image of the selected character or symbol is formed by the camera lens on a light-sensitive film in a magazine 3<SP>1</SP>, a focused image being maintained for variations in magnification by means of a double cam drum 31 on a shaft 32<SP>1</SP> rotatable by worm 33 and worm-wheel 32 from a handle 34, the cam surfaces being engaged by follower rollers 311, 3111 on the camera lens and magazine mountings 29, 30, respectively, which are slidable along longitudinal dovetail guideways on the base 19. Spacing on the film is effected by sliding movement across the camera of a rod 44 mounted in the camera body, the rod rotating a film-feeding sprocket 50 through a one-way drive. Normal spacing is effected under the control of a lever 35 pivoted at 37 on a plate 38 and moved by an electromagnet 42 and having a slot 48 in which is engaged a pin 47 on the rod 44. The extent of the movement is determined by the engagement of a blade 36 on the lever with the selected one of levers 43<SP>1</SP> controlled by electromagnets 43, also on the plate 38, in accordance with the relative width of the selected symbol while the body or point size is taken into account by the position of the pin 47 in the slot 48 which is determined by the positioning of the plate 38 under control of a screw driven by a handle 41 which also indicates the selected body size on a scale. Adjustments to the spacing, e.g. for different character widths on the same body size, may be effected by means of a handle 58 which rotates a cam 59 against which the rod 44 engages. The operation of the machine is as follows. (1) The desired character or symbol is selected by the hand wheel 8 and an image of the selected symbol becomes visible in a window 62. (2) A button 61 is depressed, releasing a lock which prevents inadvertent exposure whilst choosing the required symbol. (3) The body size required is set by handle 41, and (4) the exposure time switch 70 is set in accordance with indications of a table related to body size and film speed. (5) A button 65 is then depressed which through contacts 20<SP>1</SP> energizes electromagnet 22 to position and latch the matrix film supporting drum, the latch 21 then causing appropriate operation of the spacing device, and the lever 35 finally closing a switch for the timer 70. On completion of the exposure the parts return to rest. The operation of the spacing mechanism also causes the rod 44 to move a tape 53 by means of a one-way drive to the roller 52 and an image 69 of a transparent pointer on the tape lit by a tubular lamp 56 is made visible by an inclined reflector 57 on a double line length scale 71. By this means and an adjustable pointer 66 the line deficit may be determined. Thus if a line is first composed without exposure, a justified line can thereafter be produced by dividing the line deficit between the spaces in the line by means of the handle 58 and cam 59. A knob 68 is provided for zeroing the pointer image 69.